The invention relates to a shoe with an upper, an insole connected to the upper, a sole construction connected to the upper and a substantially waterproof lining, the upper which consists of a material of relatively high water-conductivity having connected to it a marginal strip of a material of lesser or no water conductivity which is connected to the insole and which through the interposition of a sealing-tight compound bears on the waterproof lining in a waterproof fashion, the sole structure having at least one per se watertight layer which is connected in watertight manner to the outside of the marginal strip.
Modern lining materials such as are commercially available for example under the trade mark Goretex(.RTM.), provide for the waterproof lining of shoes without impeding their permeability to vapour. Basically, two systems are known. In the case of a first system, a complete sock is inserted or rigidly incorporated into the shoe. In the case of a further system, only the upper part of the shoe is lined and watertightness is completed by connecting the lining to a sealing structure in the sole zone. The present invention is concerned with the latter-mentioned system.
It is known from German Patent Specification No. 37 12 901 for the lining material to be continued on the underside of the insole beyond the welt of the upper and to be embedded there into a waterproof coating which is sprayed onto the underside of the insole so forming a sealing-tight continuation of the lining in the sole area.
In the case of a first construction according to this Patent Specification, the upper is formed from a laminate comprising an outer layer, a vapour-permeable membrane as a middle layer and an inner layer. On the inside of the inner layer there may possibly be a lining material. The laminate engages under the insole. In the marginal area of the insole, the laminate is, via its inner layer, rigidly lasted on the insole by the AGO method. A projecting area of the laminate is disposed underneath the insole where it is embedded into a sealing material which is sprayed onto the underside of the insole. This construction is only suitable for producing special shoes in which the upper material, the waterproof membrane and the inner material form one laminate. The connection between the upper material and the insole is established by means of the waterproof membrane and the inner layer so that all the mechanical tensile loadings during production and in operation have to be transmitted through the layered construction of the laminate.
In the case of another construction according to this Patent Specification, leather can be used as the material for the upper. The waterproof lining in this case projects below the edge of the leather and underneath the insole into a sealing-tight material which is again injection moulded onto the underside of the insole. What is not clear in this case is how the mechanical connection is to be established between the insole and the upper material. Again, if one is referring to a laminate joint between the upper material and the waterproof lining, then once again the problem arises that all the tensile forces occurring in the upper material, regardless of whether they are caused during lasting or during use can only be transmitted through the layered bonding between the insole and the upper material. injection moulded onto the underside of the insole. What is not clear in this case is how the mechanical connection is to be established between the insole and the upper material. Again, if one is referring to a laminate joint between the upper material and the waterproof lining, then once again the problem arises that all the tensile forces occurring in the upper material, regardless of whether they are caused during lasting or during use can only be transmitted through the layered bonding between the insole and the upper material.
German Utility Model Specification No. 87 17 201 discloses a shoe in which the upper material is sewn to a marginal strip close to the sole and which consists of a perforated or porous material, for example a netting of synthetic fibres with a mesh size of about 1.5 mm, the threads of the netting possibly being monofilament threads, particularly monofilament polyamide or polyester threads. On its inside, the upper material is lined with a waterproof membrane which is coated with a textile layer on its inside surface which is towards the foot and also with a textile layer on its outside which is towards the upper material. Coated in this way, the membrane is then sewn to the insole together with the marginal strip which consists of a netting material. Then, a sole of waterproof synthetic plastics material is injection moulded on, the shell rim of the sole covering the marginal strip. During injection moulding, the initially liquid sole material is intended to penetrate the pores and holes in the net-like marginal strip and pass through to the outside of the lining material.
Known furthermore from EP-A1-284 638 is a shoe of which the upper consists of an outer upper material, a teflon membrane applied to the inside face of the upper material and a lining which masks the inside face of the teflon membrane. During production of this shoe, the upper which is produced in conventional manner has its ends folded around the insole and fixed to this latter by adhesion and/or by nailing. Applied to the folded-over end of the upper is an intermediate sole which consists of a filling composition and a thin rubber layer. The filling composition is glued to the insole by pressure and heat in order to fill in damage to the upper originating from the fixing and to compensate for any unevenness which may have been caused by the bent-over end on the insole. The outsole is then glued onto the intermediate sole. The intention of this method of production is to ensure that the shoe is sealed off in waterproof fashion and to ensure that the outsole no longer needs to exhibit any sealing properties.
Where this known construction is concerned, the upper material itself, unmodified, extends into the region between the insole and the outsole. If the upper material is water-conductive, in other words if it consists for instance of water-conductive leather or textile material, this means that a water-conductive layer extends into the intermediate space between the insole and the outsole. Even if it is understood that the filling composition is waterproof and prevents further penetration of the water which may have been introduced through the upper material, then it is nevertheless extremely undesirable that due to capillary action of the upper material water may constantly penetrate the intermediate space between the insole and the outsole. This water can lead to rapid rotting of the folded-over end of the upper material which is disposed between the insole and the outsole. Furthermore, the prior art method in which the filling composition is applied to the insole by pressure and heat, necessarily presupposes the presence of a mould which serves to introduce the filling composition so that the shoe manufacturer is limited in his choice of procedures.
On the basis of a shoe such as is defined at the outset the invention is based on the problem of further improving the watertightness of the shoe and of permitting a multiplicity of methods of manufacture.